FAO, 2003. Recognizing Rift Valley fever. Animal Health Manual No. 17. Food and Agriculture Organization of the United Nations (FAO). Accessed 4 October 2020.
" }, "editorialNote": { "en": [ "source:UNDRR HIPS" ] }, "scopeNote": { "en": [ "Rift Valley fever (RVF) is a viral zoonosis that primarily affects animals but also has the capacity to infect humans. Infection can cause severe disease in both animals and humans (WHO, 2018). RVF is an economically important disease, and affects different species of animals and humans. Immunisation and vector control are the main strategies to reduce the incidence of RVF. It is considered an occupational disease of livestock handlers, dairy farmers, abattoir workers and veterinarians. The direct socio-economic impact of RVF is on livestock producers due to high levels of mortality and morbidity in animals (WHO, 2018). RVF virus is a member of the Phlebovirus genus. The virus was first identified in 1931 during an investigation into an epidemic among sheep on a farm in the Rift Valley of Kenya (WHO, 2018). Since then, outbreaks have been reported in sub-Saharan Africa. In 1977 an explosive outbreak was reported in Egypt, the RVF virus was introduced to Egypt via infected livestock trade along the Nile irrigation system. In 1997–1998, a major outbreak occurred in Kenya, Somalia and Tanzania following an El Niño event and extensive flooding. After infected livestock trade from the horn of Africa, RVF spread in September 2000 to Saudi Arabia and Yemen, marking the first reported occurrence of the disease outside the African continent and raising concerns that it could extend to other parts of Asia and Europe (WHO, 2018). RVF is a disease of caused by RVF virus (RVFV), an arbovirus, transmitted by Aedes mosquitoes. RVF epidemic/epizootic has been associated with periods of flooding following heavy rainfall especially after a long drought. These floods create pools of water conducive for hatching/emergence of Aedes mosquitoes, which may be infected with the RVFV and can transmit the virus to ruminants or camels when they drink from or feed close to the water pools (FAO, 2003). Outbreaks of RVF in animals can be prevented by a sustained programme of animal vaccination. Commercially available veterinary RVF vaccines are important for preventing the spread of RVFV in endemic countries. Three live-attenuated RVF vaccines are available for veterinary use in endemic areas. However, these vaccines have adverse effects in pregnant ewes, resulting in abortion or malformation. On the other hand, three different inactivated RVF vaccines that induce short-term immunity are also available in endemic regions (FAO, 2003). Rift Valley fever outbreaks in domesticated animals are often accompanied by human disease. The majority of human infections result from contact with the blood or organs of infected animals. Human infections have also resulted from the bites of infected mosquitoes. To date, no human-to-human transmission of RVF virus has been documented (WHO, 2018). The most common form of the disease in humans is a self-limiting, flu-like illness. Complications in a minority of cases include ocular disease, neurological signs, kidney dysfunction and a life-threatening haemorrhagic syndrome with hepatic dysfunction. Although overall case fatality rates are thought to be low (≤2%), there may be a very large number of cases during some epidemics, resulting in hundreds of serious cases and significant numbers of deaths (Spickler, 2015)." ] }, "inScheme": [ { "id": "http://connectivity-hub.com/terms/", "title": { "en": "Climate Connectivity Taxonomy" } } ], "inSchemeAll": [ { "id": "http://connectivity-hub.com/terms/" } ], "topConceptOf": [ { "id": "http://connectivity-hub.com/terms/", "title": { "en": "Climate Connectivity Taxonomy" } } ], "@context": { "@version": 1.1, "id": "@id", "type": "@type", "@vocab": "http://www.w3.org/2004/02/skos/core#", "xsd": "http://www.w3.org/2001/XMLSchema#", "dct": "http://purl.org/dc/terms/", "dc": "http://purl.org/dc/elements/1.1/", "schema": "https://schema.org/", "vann": "http://purl.org/vocab/vann/", "ldp": "http://www.w3.org/ns/ldp#", "owl": "http://www.w3.org/2002/07/owl#", "title": { "@id": "dct:title", "@container": "@language" }, "dc:title": { "@id": "dc:title", "@container": "@language" }, "dc:description": { "@id": "dc:description", "@container": "@language" }, "description": { "@id": "dct:description", "@container": "@language" }, "license": { "@id": "dct:license", "@container": "@language" }, "issued": { "@id": "dct:issued", "@type": "xsd:date" }, "created": { "@id": "dct:created", "@type": "xsd:date" }, "modified": { "@id": "dct:modified", "@type": "xsd:date" }, "creator": "dct:creator", "publisher": "dct:publisher", "preferredNamespacePrefix": "vann:preferredNamespacePrefix", "preferredNamespaceUri": "vann:preferredNamespaceUri", "isBasedOn": "schema:isBasedOn", "source": "dct:source", "prefLabel": { "@container": "@language" }, "altLabel": { "@container": [ "@language", "@set" ] }, "hiddenLabel": { "@container": [ "@language", "@set" ] }, "definition": { "@container": "@language" }, "note": { "@container": [ "@language", "@set" ] }, "changeNote": { "@container": [ "@language", "@set" ] }, "editorialNote": { "@container": [ "@language", "@set" ] }, "historyNote": { "@container": [ "@language", "@set" ] }, "scopeNote": { "@container": [ "@language", "@set" ] }, "notation": { "@container": "@set" }, "example": { "@container": "@language" }, "narrower": { "@container": "@set" }, "related": { "@container": "@set" }, "relatedMatch": { "@container": "@set" }, "narrowerTransitive": { "@container": "@set" }, "broaderTransitive": { "@container": "@set" }, "broadMatch": { "@container": "@set" }, "narrowMatch": { "@container": "@set" }, "closeMatch": { "@container": "@set" }, "exactMatch": { "@container": "@set" }, "hasTopConcept": { "@container": "@set" }, "inScheme": { "@container": "@set" }, "topConceptOf": { "@container": "@set" }, "deprecated": { "@id": "owl:deprecated", "@type": "xsd:boolean" }, "isReplacedBy": { "@id": "dct:isReplacedBy", "@container": "@set" } } }